1. Field of the Invention
The present invention relates to piston rings, and in particular to rings that can be fitted into piston ring grooves during piston manufacture or can be utilized as replacement rings.
2. Prior Art
Currently, in conventional internal combustion engine and hydraulic pump applications, each piston of such engine or pump generally includes a top ring and a second ring that function as sealing rings and further includes an oil control ring spaced from the top and second rings towards the piston bottom end. During engine or pump operations, the sealing rings engage and seal against a cylinder wall to maintain cylinder pressure integrity and, as they are moved up and down in that cylinder, they each create a frictional horsepower power loss. For example, an engine that is predicted to nine hundred (900) horsepower will show approximately seven hundred (700) horsepower, true, as measured on a dynamometer. This is a difference of two hundred (200) horsepower between the theoretical and actually generated horsepower and is primarily attributable to the friction loss of contact of the sealing rings with the cylinder wall. Where the top and second rings must fit tightly against the cylinder wall, the oil control ring is comparatively loose fitting as it is intended only to apply a coating of oil onto the cylinder wall. Therefore, it is apparently the case that the top and second sealing rings are responsible for most of the friction loss. Clearly, therefore, an elimination of one of the sealing rings should provide a marked reduction in friction losses. The present invention provides a ring and seal combination assembly whereby, with a single sealing ring assembly only, cylinder head pressures will be properly contained during engine operation, with the utilization of a single sealing ring only providing a significant improvement in engine efficiency over earlier pairs of seal ring arrangements, such as those that utilize the described top and second sealing rings.